# How to power raspberry pi via Adafruit 20w Amp? **URL:** \ **Category:** Adafruit\ **Created:** [21 October 2019 03:32 UTC](https://forum.core-electronics.com.au/t/how-to-power-raspberry-pi-via-adafruit-20w-amp/6667 "2019-10-21T03:32:32Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![Peter101385](https://avatars.discourse-cdn.com/v4/letter/p/c6cbf5/32.png) [@Peter101385](https://forum.core-electronics.com.au/u/Peter101385)\ **Post date:** [21 October 2019 03:32 UTC](https://forum.core-electronics.com.au/t/how-to-power-raspberry-pi-via-adafruit-20w-amp/6667/1 "2019-10-21T03:32:32Z")
Hi I am building a Raspberry Pi speaker. I’m using gan old Raspberry Pi Model B (revision 2.0) which is already running Shareport Sync. I’d like to hook up my Raspberry Pi to the Adafruit Stereo 20W Class D Audio Amplifier - MAX9744, but also have them utilising the same power supply. From what I’ve read online this is possible, but I am unsure how exactly to do this. I have some thoughts, and am hoping someone can tell me if I’m wrong - here are the steps I think are needed: Connect MAX9744 Amp to power supply 12V DC 5A (e.g. [https://core-electronics.com.au/12v-5a-switching-power-supply-45158.html](https://core-electronics.com.au/12v-5a-switching-power-supply-45158.html)) Wire the VDD and GND pins on the MAX9744 Amp to a step down regulator: > **[Pololu 5V Step-Up/Step-Down Voltage Regulator S9V11F5](https://core-electronics.com.au/5v-step-up-step-down-voltage-regulator-s9v11f5.html)** > > The S9V11F5 switching step-up/step-down regulator efficiently produces 5 V from input voltages between 2 V and 16 V. (Note: it requires an input voltage of at least 3 V to start, but it can operate down to 2 V after startup.) or > **[Mini DC/DC Step-Down (Buck) Converter - 5V @ 1A output - TSR12450](https://core-electronics.com.au/mini-dc-dc-step-down-buck-converter-5v-at-1a-output-tsr12450.html)** > > Your power supply problems just got SOLVED! These DC/DC converter step-down switching regulators are drop-in replacements for inefficient 78xx linear regulators. .. read more The step down regulator will in turn be wired to a micro USB plug ([https://core-electronics.com.au/usb-diy-connector-shell-type-micro-b-plug.html](https://core-electronics.com.au/usb-diy-connector-shell-type-micro-b-plug.html)) which will then power the Raspberry Pi (with protections still in place) Questions: Will this set up work? Which step down regulator is best? The voltage regulator sounds less efficient, and I read it may cause heat. It only has 1.5A as well. Is this enough for the Pi? The buck convertor seems to be more efficient, but has only 1A - so same question for whether this will power the Pi? I am planning to use the MAX9744 Amp in analog mode. But want to check that if I set the Amp at some max volume level using the the potentiometer, I will still be able to control the volume at the source (i.e. from the Pi running over AirPlay)? Cheers ---
**Author:** ![Robin57159](https://avatars.discourse-cdn.com/v4/letter/r/cc9497/32.png) [@Robin57159](https://forum.core-electronics.com.au/u/Robin57159)\ **Post date:** [22 October 2019 01:51 UTC](https://forum.core-electronics.com.au/t/how-to-power-raspberry-pi-via-adafruit-20w-amp/6667/2 "2019-10-22T01:51:22Z")
If you don’t have one lieing around, don’t forget the IEC power cable for the power supply. > **[2m IEC C13 10A 3 Pin Black Appliance Mains Lead](https://core-electronics.com.au/2m-iec-c13-10a-3-pin-black-appliance-mains-lead.html)** > > IEC Female to 3 Pin 2m. Energy authority approved Consider this DC-DC converter. Capable of the 3A recommended for the RPi. > **[DC-DC Buck-Mode Power Module (8~28V to 5V 3A)](https://core-electronics.com.au/dc-dc-buck-mode-power-module-8-28v-to-5v-3a.html)** > > This is a DC-DC buck-mode power module, with input voltage range 8V~28V and fixed output voltage/current 5V/3A. Its work frequency can reach to 0.5MHz. The module .. read more Perhaps a splitter cable to split the output of the power supply, and a couple of barrel Jack’s? > **[2-Way 2.1mm DC Barrel Jack Splitter Squid](https://core-electronics.com.au/2-way-2-1mm-dc-barrel-jack-splitter-squid.html)** > > Double up your power adapters with this wonderfully simple 2-way power jack splitter. All you have to do is connect a standard 5.5mm/2.1mm sized plug into one end, .. read more > **[DC Barrel Jack Adapter - Female](https://core-electronics.com.au/dc-barrel-jack-adapter-female.html)** > > This adapter allows you to connect a barrel jack connector to bare wires. One end has screw terminals and the other has a 5.5x2.1mm, center-positive female barrel jack. > **[MicroUSB Plug to 5.5/2.1mm DC Barrel Jack Adapter](https://core-electronics.com.au/microusb-plug-to-5-5-2-1mm-dc-barrel-jack-adapter.html)** > > The premise of this MicroUSB Plug to 5.5/2.1mm Jack adapter is simple. There's a MicroUSB plug on one end and a 5.5mm/2.1mm DC barrel jack with center positive polarity .. read more